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CN-121983714-A - Battery control method, controller, battery pack and electric equipment

CN121983714ACN 121983714 ACN121983714 ACN 121983714ACN-121983714-A

Abstract

The embodiment of the application provides a battery control method, a controller, a battery pack and electric equipment. The method comprises the steps of controlling the battery to perform self-heating when the temperature of the battery is lower than a first temperature, wherein the self-heating current meets the following conditions: wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC. On the basis of improving the heating efficiency of self-heating, the lithium separation risk is reduced, the retention rate of the battery capacity is improved, the quick charge time is shortened, and the service life of the battery is prolonged.

Inventors

  • XIAO JING
  • DENG JIE
  • LENG JINGNING
  • CHEN NA
  • HE LONG

Assignees

  • 比亚迪股份有限公司

Dates

Publication Date
20260505
Application Date
20260331

Claims (15)

  1. 1. A battery control method, characterized in that the method comprises: When the temperature of the battery is lower than a first temperature, controlling the battery to perform self-heating, wherein the self-heating current meets the following conditions: ; Wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC.
  2. 2. The method of claim 1, wherein the step of determining the position of the substrate comprises, 。
  3. 3. The method according to claim 1, wherein the heating current has a frequency denoted f in Hz, 。
  4. 4. The method of claim 1, wherein the first temperature is greater than or equal to-30 ℃ and less than or equal to 20 ℃.
  5. 5. The method of claim 1, wherein the positive electrode of the cell has a double-sided density of σ1 in g/m 2 , 300 1000, And/or the negative electrode of the battery has a double-sided density sigma 2 in g/m 2 , 130 460; And/or the positive electrode of the battery has compacted density of gamma 1, g/cm 3 , 2.2 3, And/or the negative electrode of the battery has a compacted density of gamma 2 in g/cm 3 , 1.4 2。
  6. 6. The method of any one of claims 1-5, wherein the waveform of the heating current comprises at least one of a sine wave, a square wave, a trapezoid wave, and a triangle wave.
  7. 7. The method according to any one of claims 1 to 5, wherein the mass percentage of the binder of the battery is denoted as ω, 。
  8. 8. The method according to any one of claims 1 to 5, wherein the mass ratio of the conductive agent of the battery is expressed as ,0 3 。
  9. 9. The method according to any one of claims 1-5, further comprising: and charging the battery by adopting a charging current under the condition that the battery is self-heated to a second temperature.
  10. 10. A battery control method, characterized by being applied to an electric vehicle having a charging interface and a battery, the method comprising: When the charging interface is connected with external charging equipment and the temperature of the battery is lower than a first temperature, the battery is controlled to be self-heated, and the self-heating current meets the following conditions: ; Wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC.
  11. 11. A battery control method, characterized by being applied to a charging device, comprising: when the charging equipment is connected with external electric equipment and the temperature of a battery of the external electric equipment is lower than a first temperature, the battery is controlled to be self-heated, and the self-heated heating current meets the following conditions: ; Wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC.
  12. 12. A battery pack comprising a battery; when the temperature of the battery is lower than a first temperature, self-heating is carried out, and the self-heating current meets the following conditions: ; Wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC.
  13. 13. A controller is characterized by comprising a memory and a processor; the memory stores computer-executable instructions; the processor executing computer-executable instructions stored in the memory, causing the processor to perform the method of any one of claims 1-11.
  14. 14. A battery pack comprising a battery and the controller of claim 13.
  15. 15. A powered device comprising the battery pack of claim 14 or the controller of claim 13.

Description

Battery control method, controller, battery pack and electric equipment Technical Field The present application relates to the field of batteries, and in particular, to a battery control method, a controller, a battery pack, and electric devices. Background The rapid charging of lithium ion batteries in low temperature environments can cause problems of life decay of lithium ion batteries. The core mechanism of the lithium ion battery is that when the lithium ion battery is charged rapidly, the lithium ion concentration at the interface of the negative electrode is increased sharply, the interface polarization is increased remarkably, further, lithium metal is induced to deposit on the negative electrode, the deposited lithium metal can aggravate interface contact failure, a high-impedance interface layer is generated, lithium ion transmission is hindered, the lithium ion intercalation/deintercalation process is hindered, the available active substances of the lithium ion battery are reduced, the capacity of the lithium ion battery is reduced rapidly, and the capacity retention rate of the lithium ion battery is lower. In order to alleviate the above problems, the related art adopts heating current to perform self-heating, and increases the temperature of the battery core by increasing the current multiplying power so as to heat the battery core to a higher temperature for recharging, thereby enhancing the lithium ion transmission kinetics, realizing the inhibition of lithium precipitation and prolonging the service life of the battery. However, the self-heating using the heating current in the related art has a problem of increasing the risk of lithium precipitation or decreasing the heating efficiency. Therefore, there is a need for a battery control method that reduces the risk of lithium precipitation while satisfying the heating efficiency of self-heating, and maintains a high capacity retention rate of the battery to maintain a high lifetime of the battery. Disclosure of Invention The embodiment of the application provides a battery control method, a controller, a battery pack and electric equipment, which are used for reducing the lithium separation risk on the basis of meeting the heating efficiency of self-heating, and keeping the battery to have higher capacity retention rate so as to maintain the battery to have longer service life. In a first aspect, an embodiment of the present application provides a battery control method, including: When the temperature of the battery is lower than a first temperature, controlling the battery to perform self-heating, wherein the self-heating current meets the following conditions: ; Wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC. In one possible implementation of the method according to the invention,。 In one possible embodiment, the frequency of the heating current is denoted as f, in Hz,。 In one possible embodiment, the first temperature is greater than or equal to-30 ℃ and less than or equal to 20 ℃. In one possible embodiment, the positive electrode of the battery has a double-sided density denoted as sigma 1 in g/m 2, 3001000, And/or the negative electrode of the battery has a double-sided density sigma 2 in g/m 2, 130460。 In one possible embodiment, the waveform of the heating current includes at least one of sine wave, square wave, trapezoidal wave, and triangular wave. In one possible embodiment, the mass percentage of the binder of the battery is denoted ω,。 In one possible embodiment, the mass ratio of the conductive agent is recorded as,03。 In one possible embodiment, the positive electrode of the battery has a compacted density denoted by gamma 1 in g/cm 3, 2.23, And/or the negative electrode of the battery has a compacted density of gamma 2 in g/cm 3, 1.42。 In one possible embodiment, the battery is charged with a charging current in the event that the battery self-heats to a second temperature. In a second aspect, an embodiment of the present application provides a battery control method, applied to an electric vehicle, where the electric vehicle has a charging interface and a battery, the method includes: When the charging interface is connected with external charging equipment and the temperature of the battery is lower than a first temperature, the battery is controlled to be self-heated, and the self-heating current meets the following conditions: ; Wherein the ratio of the peak value to the valley value of the current value of the heating current is recorded as The initial state of charge of the battery, which is self-heating, is noted as SOC. In a third aspect, an embodiment of the present application provides a battery control method, applied to a charging device, including: when the charging equipment is connected with external electric equipment and the temperature of a battery of the ext